H and E Staining Procedures
D4 H and E staining procedures
Haematoxylin and eosin staining is a technique used by pathologists to add definition to nuclei and other parts of a cell in tissue samples under a microscope so that they can see it better when analysing the cells form and abnormalities. The H&E technique is the most commonly used in histology and the diagnoses of malignancies is based largely on the results of this procedure. The dyes will specifically stain elements of a cell or tissue because the dyes have a high affinity for molecules in the cells and tissues; this is the attractive forces between the dye and the molecules within the tissue. Dyes have bigger affinities for tissue cells than solvent molecules.
Haematoxylin solutions are used to add blue colour to the nuclei of cells and a few other objects such as keratohyalin granules. The stain contains either aluminium or iron which fixes it to the cells nuclei forming dye-mordant tissue complexes. The dye binds to the nucleus because the chromatic material in the nucleus is strongly negative and the haematin and aluminium inside the haematoxylin is positive therefore the die is attracted to the nuclei and any other negatively charged molecules in the cells and is repelled by the other parts. When staining tissue with heamatoxylin dyes the background can sometimes be partially dyed to, this can be reduced or completely removed by differentiation using acidic solutions to decrease the hematoxylins ability to bind to tissue sites.
When staining with haematoxylin it can be done regressively or progressively. In regressive staining the stain is applied and over stained so the background get stained too, a differentiator is used aggressively to removes excess haematoxylin and then the normal stain procedure carries on with the eosin counter stain.
Progressive staining is where the tissue has only a certain amount of haematoxylin stain applied so that there is no excess to be removed by a differentiator the tissue is just
Haematoxylin and eosin staining is a technique used by pathologists to add definition to nuclei and other parts of a cell in tissue samples under a microscope so that they can see it better when analysing the cells form and abnormalities. The H&E technique is the most commonly used in histology and the diagnoses of malignancies is based largely on the results of this procedure. The dyes will specifically stain elements of a cell or tissue because the dyes have a high affinity for molecules in the cells and tissues; this is the attractive forces between the dye and the molecules within the tissue. Dyes have bigger affinities for tissue cells than solvent molecules.
Haematoxylin solutions are used to add blue colour to the nuclei of cells and a few other objects such as keratohyalin granules. The stain contains either aluminium or iron which fixes it to the cells nuclei forming dye-mordant tissue complexes. The dye binds to the nucleus because the chromatic material in the nucleus is strongly negative and the haematin and aluminium inside the haematoxylin is positive therefore the die is attracted to the nuclei and any other negatively charged molecules in the cells and is repelled by the other parts. When staining tissue with heamatoxylin dyes the background can sometimes be partially dyed to, this can be reduced or completely removed by differentiation using acidic solutions to decrease the hematoxylins ability to bind to tissue sites.
When staining with haematoxylin it can be done regressively or progressively. In regressive staining the stain is applied and over stained so the background get stained too, a differentiator is used aggressively to removes excess haematoxylin and then the normal stain procedure carries on with the eosin counter stain.
Progressive staining is where the tissue has only a certain amount of haematoxylin stain applied so that there is no excess to be removed by a differentiator the tissue is just
References: • “H&E staining” video from http://www.youtube.com/watch?v=2D0rj0m6dVs . by ABNOVA1. Date accessed 23/05/13 • “The science and application of haematoxylin and eosin staining” by the Robert H. Lurie Comprehensive Cancer Centre at North-western University. PowerPoint from http://www.feinberg.northwestern.edu/research/docs/cores/mhpl/HandE_troubleshooting.pdf . date accessed 23/05/13